JP2002106437A - Air intake muffler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air intake muffler relatively easy to manufacture. SOLUTION: The air intake muffler is provided with a single tube duct body 41a, an air intake duct 41 having a flange part 43 set at an end thereof and an outside casing 44 extruding from an outer perimeter of the flange part, an air intake duct connecting aperture 37, an inside pipe 38 extruding outwards from an edge part of the air intake duct connecting aperture and air intake related parts 1 having an outside pipe 39 fitted coaxially into the air intake duct connecting aperture and having an outside diameter greater than an diameter of the air intake duct connecting aperture. When the air intake duct is connected with the air intake related parts 1, an outside casing of the air intake duct is fitted into outside pipe of the air intake related parts, an double tube structure is formed at a connection part of the air intake and the air intake related parts 1, the outside casing of the double tube structure and spacing between the outside pipe and the inside pipe become a muffler chamber 53 and also a communicating aperture 38a formed in the inside pipe communicates with inside spacing of the inside pipe and the muffler chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake muffler provided in an intake system of an internal combustion engine (particularly, an automobile engine).

[0002]

2. Description of the Related Art The intake air silencer is provided in an intake system of an engine and has a function of reducing intake air pulsation noise of the engine. 7 is a cross-sectional view of a conventional intake silencer, FIG. 7A is an explanatory diagram of a first conventional example, and FIG. 7B is an explanatory diagram of a second conventional example. In the first conventional example shown in FIG. 7A, first, the intake duct 01 is injection-molded with resin or the like, and then, with the intake duct 01 inserted, the case 03 of the sound deadening chamber 02 is blow-molded with resin or the like. Has formed. In addition, a sound deadening chamber 02 is provided in the intake duct 01.
A circular hole 04 is formed that communicates with the space in the intake duct 01. The first connection port 05 of the intake duct 01 having the sound deadening chamber 02 formed in this way is connected to the connection port 07 of the air cleaner 06 via the rubber duct 08. The second connection port 011 of the intake duct 01 is connected to an intake system of the engine such as an intake pipe (not shown) via a rubber duct 012.

In the second conventional example shown in FIG. 7B,
A left muffling member 023 composed of a left intake duct 021 and a left muffling chamber case 022 is integrally formed of resin or the like, and a right muffling member composed of a right intake duct 027 and a right muffling chamber case 028 having a cutout 026 as a communication opening. 029 integrally formed of resin or the like, and the left
23 and the right silencing member 029 are abutted and welded together to be integrated. And, like the first conventional example,
The air cleaner 06 and an intake system of the engine such as an intake pipe are connected through rubber ducts 08 and 012.

[0004]

In such a conventional example,
The intake ducts 01, 021, 027 pass through the box-shaped cases 03, 022, 028 of the sound deadening room 02. Therefore, the structure and the manufacturing process are complicated. In addition, intake duct 0
1,021,027 needs to be connected to the air cleaner 06, which is an intake system part, via the rubber ducts 08,012, and the number of parts increases, and the cost increases.

[0005] The present invention has been made in view of the above problems, and has an object of the following description (1). (1) To provide an intake silencer having a small number of parts and easy to manufacture.

[0006]

Means for Solving the Problems (First Invention) The first invention of the present application
The intake air silencer of the present invention has a single pipe duct body (41).
a), an intake duct () having a ring-shaped flange (43) provided at an end of a duct body (41a) of the single pipe and an outer cylindrical portion (44) protruding from an outer peripheral portion of the flange (43). 41), an intake duct connection opening (37), an inner pipe (38) protruding outward from an edge of the intake duct connection opening, and the intake duct connection opening (3).
An intake system component (1) including an outer pipe (39) having a diameter larger than the diameter of (7), and a communication opening (38a) formed in the inner pipe (38). When the intake duct (41) and the intake system component (1) are connected, the outer cylindrical portion (4) of the intake duct (41) is connected.
4) and the outer pipe (39) of the intake system component (1) are fitted to form a double-pipe structure at the connection between the intake duct (41) and the intake system component (1). The space between the outer pipe part (44) and the outer pipe (39) forming the double pipe structure and the inner pipe (38) becomes a sound deadening chamber (53), and the communication opening (38a) is formed in the inner pipe. The internal space of (38) communicates with the sound deadening chamber (53).

(Second Invention) A suction muffler according to a second invention of the present application is a single pipe duct body (41a), and a ring-shaped flange provided at an end of the single pipe duct body (41a). (43) an intake duct (41) having an outer cylindrical portion (44) protruding from an outer peripheral portion of the flange portion (43) and an inner cylindrical portion (61) protruding from an inner peripheral portion of the flange portion (43); An intake pipe part (1) including an intake duct connection opening (37), and an outer pipe (39) having a diameter larger than the diameter of the intake duct connection opening (37); 61) and a communication opening (61a). When the intake duct (41) and the intake system component (1) are connected, the intake duct (41)
Of the intake system part (1) and the outer pipe (39) of the intake system part (1) are fitted together to form a double pipe structure at the connection between the intake duct (41) and the intake system part (1). The space between the outer tube (44) and the outer pipe (39) and the inner tube (61) forming the double pipe structure is formed in the sound deadening chamber (5).
3), and the communication opening (61a) communicates the internal space of the inner cylinder portion (61) with the sound deadening chamber (53).

In the intake silencer according to the present invention (the first invention and the second invention) having the above configuration, when the intake duct (41) and the intake system component (1) such as an air cleaner are connected, the intake duct is constructed. A double pipe structure is formed at the connection between the (41) and the intake system component (1). Air to the engine flows while pulsating in the center space of the double pipe structure, and the outer pipe of the double pipe structure (that is, the outer cylinder portion 44 and the outer pipe 39) and the inner pipe (that is, the inner pipe) The space between the pipe 38 and the inner cylinder part (61) becomes the sound deadening chamber (53).
The sound deadening chamber (53) and the space in the inner pipe (38 or 61) communicate with each other through a communication opening (38a or 61a) formed in the inner pipe (38 or 61), and a coaxial resonator is formed. It is configured to suppress intake pulsation noise.

In the air intake silencer according to the first aspect of the present invention, the flange (43) is provided with a fitting portion for fitting to an inner or outer peripheral surface of a distal end of the inner pipe (38). (38a) can be formed by a notch (38a) formed at the tip of the inner pipe (38). In this case, the communication opening (38) is formed by the notch (38a).
a) can be easily formed, and the configuration of the mold can be simplified. Further, the fitting part is a step part (41b).
And the engagement groove (56) can be easily formed, and the inner pipe (38) of the air cleaner (1) can be reliably positioned by the fitting portion. Notch (38a) of sound deadening room (53)
Can be prevented from communicating with the intake path at other times.

In the second aspect of the present invention, the inner cylindrical portion (6) is provided on an outer peripheral portion of the intake duct connection opening (37).
A fitting portion may be provided for fitting to the inner peripheral surface or the outer peripheral surface of the distal end of 1), and the communication opening (61a) may be formed by a cutout (61a) formed at the distal end of the inner cylindrical portion (61). In this case, the communication opening (61a) can be easily formed by the notch (61a), and
The configuration of the mold is simplified. Further, the fitting portion can be easily formed by forming an engaging groove (62) or the like, and the fitting portion makes it possible to form a distal end portion of the inner cylindrical portion (61) of the intake duct (41). Can be reliably positioned, and communication with the intake path other than the cutout portion (61a) of the muffling chamber (53) can be prevented.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific examples (embodiments) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. (Embodiment 1) FIG. 1 is a sectional view of a main part of an intake air silencer according to Embodiment 1 of the present invention. FIG. 3 is a perspective view of the air cleaner with the intake duct removed. FIG. 2 is an exploded perspective view of the intake duct and the air cleaner.

An air cleaner 1, which is an intake system component, is made of resin and has a lower case 2 having an open upper surface, a lid 3 for covering the upper surface opening of the lower case 2, the lower case 2 and the lid 3 It has a seal 4 and a filter 5 sandwiched between them. The lower case 2 and the lid 3
Are divided into three by a partition wall, and when assembled with the seal 4 and the filter 5 interposed therebetween, a filter chamber 6 divided vertically by the filter 5,
It is divided into three sound absorbing chambers 7 and 8. The lower case 2 of the air cleaner 1 is provided with a communication path 7a for communicating the lower part of the filter chamber 6 with the sound absorbing chamber 7, and a communication path 8a for communicating the lower part of the filter chamber 6 with the sound absorbing chamber 8. I have.

Further, an air inlet 11 is provided in the lower case 2, and an air inlet pipe 12 is connected to the air inlet 11 via a connection pipe 13. This air introduction pipe 1
2 has a case 16 whose upper surface is open, and a lid 17 which covers the upper surface of the case 16. And Case 1
The inner space of 6 and the lid 17 is vertically partitioned by a partition plate 18. A large pipe 21 and a small pipe 22 penetrating vertically are formed integrally with the partition plate 18. An air introduction passage 19 is formed in a space between the partition plate 18 and the lid 17, and a side branch type sound absorbing chamber 20 is formed by a space between the partition plate 18 and the case 16.

The lid 3 of the air cleaner 1 has
An intake duct connection 36 is provided. An intake system component connection portion 42 of an intake duct 41 is detachably connected to the intake duct connection portion 36 of the air cleaner 1. Details of the intake duct connection portion 36 and the intake system component connection portion 42 will be described later. The intake duct 41 is made of elastic rubber or resin, is integrally formed, and has the other end connected to an intake system of an engine (not shown) such as an automobile engine.

When the engine (not shown) is operated, the air in the engine room is moved from the air introduction passage 19 of the air introduction pipe 12 with the side branch type sound absorbing chamber 20 to the connection pipe 13 and the connection pipe 13 with the opening and closing of the engine valve. The air flows into the lower part of the filter chamber 6 with pulsation through the air inlet 11 of the air cleaner 1, is filtered by the filter 5, and flows to the upper part of the filter chamber 6. The air in the upper part of the filter chamber 6 flows from the intake duct connection portion 36 to the intake duct 41, and flows into the engine body via an intake pipe (not shown).

Further, the air flow flowing through the air introduction passage 19 above the partition plate 18 pulsates as the engine valve opens and closes. Acoustic impedance determined by the cross-sectional area, length, and the like of a hole that is transmitted into the sound absorbing chamber 20 and communicates the sound absorbing chamber 20 and the air introduction path 19 and the sound absorbing chamber 2
Attenuated according to zero volume. Further, similarly to the air introduction pipe 12 communicating with the sound absorbing chamber 20, the air pressure fluctuation in the lower part of the filter chamber 6 communicating with the sound absorbing chambers 7, 8 is similarly attenuated. Therefore, intake noise is reduced.

Next, an intake duct connection portion 36 of the air cleaner 1 and an intake system component connection portion 42 of the intake duct 41.
Will be described. A substantially circular intake duct connection opening 37 is formed in the intake duct connection portion 36 of the air cleaner 1, and a substantially cylindrical inner pipe 38 protrudes outward from an edge of the intake duct connection opening 37. At the tip of the inner pipe 38, four cutouts 38a are formed as communication openings. Further, the air cleaner 1 is provided with an outer pipe 39 having a larger diameter than the inner pipe 38 and the opening 37 for connecting the intake duct, concentrically with the inner pipe 38.
The inner surface at the base of the inner pipe 38 is rounded R to reduce the resistance to air flow. The intake duct connection opening 37, the inner pipe 38, the outer pipe 39, and the like constitute an intake duct connection portion 36 of the air cleaner 1.

The intake duct 41 is a single pipe duct body 4.
1a, a ring-shaped flange 43 provided at an end of the single-tube duct main body 41a, and an outer cylindrical portion 44 protruding from an outer peripheral portion of the flange 43. The flange 43 and the outer cylinder 44 constitute an intake system component connection 42 of the intake duct 41. A step portion 41 b is formed in a ring shape at an inner edge of the flange portion 43 of the intake duct 41. The inner diameter of the outer cylinder portion 44 is formed to be larger than the inner diameter of the duct body 41a, and is substantially the same as the outer diameter of the outer pipe 39 of the air cleaner 1. The inner diameter of the intake duct main body 41a is substantially the same as the inner diameter of the inner pipe 38 of the air cleaner 1.

When the connection part 42 of the intake system of the intake duct 41 is attached to the connection part 36 of the air cleaner 1, the outer cylinder 44 of the intake duct 41 is fitted to the outer pipe 39 of the air cleaner 1. The outer cylinder 44
Is tightened with a band 51 from the outside. Further, the tip of the inner pipe 38 of the air cleaner 1 abuts the step 41b on the inner edge of the flange 43, and has a double pipe structure. A muffling chamber 53 is formed between them. In addition, the outer peripheral surface of the tip of the inner pipe is fitted to a cylindrical inner peripheral surface formed by connecting to the outer edge of the step portion 41b. The notch 38a of the inner pipe 38 becomes a communication opening, and the sound deadening chamber 53 and the inner pipe 3
8 communicates with the internal space. The silencing chamber 53 and the notch 38a function as a coaxial resonator.
Pulsating noise is reduced by the resonance effect. The set frequency of the resonator (that is, the resonance frequency)
The size is adjusted according to the size of the muffling room. In this manner, a coaxial resonator can be configured by simply connecting the intake duct 41 to the air cleaner 1.

As described above, in the first embodiment, the intake system component connection portion 42 of the intake duct 41 has the outer cylinder portion 44 and the flange portion 43, while the intake duct connection portion 36 of the air cleaner 1 has It has a duct connection opening 37, an inner pipe 38, and an outer pipe 39, and a resonator is configured by connecting the intake system component connection section 42 and the intake duct connection section 36. Therefore, occurrence of troublesome steps such as a welding step and an insert molding step is reduced. Further, since the connecting portion between the intake duct 41 and the air cleaner 1 is used, the number of parts can be reduced. Further, since the communication opening of the sound deadening chamber 53 is formed by the cutout portion 38a, the communication opening can be easily formed, and the configuration of the mold can be simplified. Since the step 41 b is formed at the inner edge of the flange 43 of the intake duct 41, the inner pipe 38 of the air cleaner 1 can be reliably positioned, and the notch of the sound deadening chamber 53 is formed. Communication with the intake path in other places is prevented.

(Embodiment 2) FIG. 4 is a sectional view of Embodiment 2 of the intake air silencer of the present invention. In the description of the second embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and a detailed description thereof will be omitted.

FIG. 4 is a view corresponding to FIG. 1 of the first embodiment, in which an engagement groove 5 is formed at an end of an outer cylindrical portion 44 of the intake duct 41.
6 is formed, and the tip of the outer pipe 39 of the air cleaner 1 is fitted into the engagement groove 56. Therefore, the outer peripheral surface and the inner peripheral surface of the distal end portion of the outer cylindrical portion 44 are fitted to the cylindrical outer peripheral surface and the inner peripheral surface forming the engagement groove 56, respectively. In the second embodiment, the band 51 is not provided, and after the engagement groove 56 and the tip of the outer pipe 39 are engaged with each other, the intake duct 41 is fixed by appropriate means. For example, the intake duct main body 41a is attached to the engine main body with a support frame or the like. The function as a resonator is substantially the same as that of the first embodiment.

(Embodiment 3) FIG. 5 is a sectional view of Embodiment 3 of the intake air silencer of the present invention. In the description of the third embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and a detailed description thereof will be omitted.

FIG. 5 is a view corresponding to FIG. 1 of the first embodiment, in which an inner cylindrical portion 61 protrudes from the inner peripheral portion of the flange 43 of the intake duct 41. Is formed with a notch 61a as a communication opening. The inner pipe 38 is not provided in the air cleaner 1, and an engagement groove 62 with which the tip of the inner cylindrical portion 61 is engaged is formed at an edge of the intake duct connection opening 37. The outer peripheral surface and the inner peripheral surface of the distal end of the inner cylindrical portion 61 are fitted to the cylindrical outer peripheral surface and the inner peripheral surface forming the engagement groove 62, respectively. The notch 61a of the inner cylinder 61 has the same function as the notch 38a of the inner pipe 38. The inner diameter of the inner cylindrical portion 61 is the same as the body 41 a of the intake duct 41.
Is formed to be substantially the same as the inner diameter of. The function as a resonator is substantially the same as that of the first embodiment.

As described above, according to the third embodiment, the connection part 42 of the intake system of the intake duct 41 includes the outer cylinder 44 and the inner cylinder 6.
1 and a flange 43, while the intake duct connecting portion 36 of the air cleaner 1 has an intake duct connecting opening 37 and an outer pipe 39, and connects the intake system component connecting portion 42 and the intake duct connecting portion 36 to each other. By connecting, a resonator is configured. Therefore, occurrence of troublesome steps such as a welding step and an insert molding step is reduced. Further, since the communication opening of the muffling chamber 53 is formed by the cutout portion 61a, the communication opening can be easily formed, and the configuration of the mold can be simplified. Since the engagement groove 62 is formed in the air cleaner 1,
The inner cylinder portion 61 of the intake duct 41 can be reliably positioned.

(Embodiment 4) FIG. 6 is a sectional view of Embodiment 4 of the intake air silencer of the present invention. In the description of the fourth embodiment, components corresponding to the components of the third embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 6 is a view corresponding to FIG. 5 of the third embodiment, in which the outer cylinder portion 44 of the intake duct 41 is fitted inside the outer pipe 39 of the air cleaner 1, and a band is formed from outside the outer pipe 39. It is fastened at 51 and fixed detachably. The function as a resonator is substantially the same as that of the third embodiment.

In each of the above embodiments, since the resonator is formed using the connection between the air cleaner and the intake duct as the intake system components, the number of components is reduced.

Although the embodiments of the present invention (specific examples of the embodiments) have been described in detail, the present invention is not limited to the above-described embodiments, and the present invention is not limited to the embodiments described in the claims. Various changes can be made within the scope of the gist. Modification examples of the present invention are exemplified below. (1) The intake system components connected to the intake duct 41 are not limited to the air cleaner 1, but may be other intake system components. For example, a pipe-integrated resonator can be used. (2) The communication opening of the muffling chamber 53 is formed by the cutout portion 38a of the inner pipe 38, but may have another structure. For example, a hole may be formed in the inner pipe 38 or the like. Further, the number of communication openings can be appropriately selected. (3) As long as the method of fixing the connection between the intake system component connection section 42 of the intake duct 41 and the intake duct connection section 36 of the air cleaner 1 is detachable, an appropriate means can be selected. (4) The material of the air cleaner 1 and the intake duct 41 can be appropriately selected. However, in order to tighten the band, in the first and third embodiments, it is preferable that the intake duct 41 is formed of an elastic resin or rubber, while the air cleaner 1 is formed of a hard resin. . In the fourth embodiment, the intake duct 41 is preferably formed of a hard resin or metal, while the air cleaner 1 is preferably formed of an elastic resin. (5) The structure of the inner pipe 38 of the air cleaner 1 or the inner cylindrical portion 61 of the intake duct 41 can be appropriately changed if the connection between the air cleaner 1 and the intake duct 41 has a double-pipe structure. . For example, a gap may be formed between the tip of the inner pipe 38 and the intake duct 41 or between the tip of the inner cylinder 61 and the air cleaner 1. However, preferably, the tip of the inner pipe 38 of the air cleaner 1 is in contact with or is engaged with the inner edge of the flange 43 of the intake duct 41, or the inner cylinder 61 of the intake duct 41 is 1 abuts or engages. (6) In the first embodiment, the tip of the inner pipe 38 is
b, and the outer peripheral surface of the distal end of the inner pipe 38 is fitted to the cylindrical inner peripheral surface formed by connecting to the outer edge of the step portion 41b. 43
Can be adopted. At this time, it is possible to provide the flange 43 with a fitting portion that fits on the outer circumference or the inner circumference of the distal end of the inner pipe 38 that comes into contact with the flange 43. Note that the fitting portion may be omitted. (7) In the third and fourth embodiments shown in FIGS.
Instead of the engaging groove 62 with which the tip end of the inner cylindrical portion 61 engages, a stepped portion fitted on the outer peripheral surface or the inner peripheral surface is provided,
2, it is possible to adopt a structure in which the front end of the inner cylindrical portion 61 is brought into contact with the outer peripheral portion of the intake duct connection opening 37 only. (8) In the embodiment, the case where the sound deadening chamber is concentric and annular has been described. However, the sound deadening chamber is not concentric but may be shifted in axial center, or may be elliptical or rectangular.

[0030]

According to the first aspect of the present invention, the main body of the intake duct is a single pipe, and a flange is formed at an end of the single pipe. , While the intake system component includes an intake duct connecting opening, an inner pipe projecting outward from an edge of the intake duct connecting opening, and concentric with the intake duct connecting opening. And an outer pipe having a diameter larger than the diameter of the intake duct connection opening, and a communication opening is formed in the inner pipe. Then, when the intake duct and the intake system component are connected, the outer cylindrical portion of the intake duct and the outer pipe of the intake system component are fitted to each other, and the connection portion between the intake duct and the intake system component is doubled. A pipe structure is formed, and the outer cylindrical portion of the double pipe structure and the space between the outer pipe and the inner pipe serve as a muffling chamber, and the communication opening communicates the inner space of the inner pipe with the muffling chamber. ing. Therefore, by simply connecting the intake duct and the intake system components, a coaxial resonator is formed, and intake pulsation noise can be suppressed. In addition, when manufacturing this air intake silencer, the need for complicated steps such as a welding step and an insert molding step is reduced. As a result, manufacture is relatively easy.

According to the intake muffler of the second invention,
In the intake duct, the main body is a single pipe, and a flange is formed at an end of the single pipe. An outer cylindrical portion protrudes from an outer peripheral portion of the flange, and an inner tube extends from an inner peripheral portion of the flange. The cylindrical portion protrudes, while the intake system component includes an intake duct connection opening, and an outer pipe concentric with the intake duct connection opening and having a diameter larger than the diameter of the intake duct connection opening. A communication opening is formed in the inner cylindrical portion. Then, when the intake duct and the intake system component are connected, the outer cylindrical portion of the intake duct and the outer pipe of the intake system component are fitted to each other, and the connection portion between the intake duct and the intake system component is doubled. A pipe structure is formed, and the space between the outer tube portion and the outer pipe and the inner tube portion of the double tube structure serves as a muffling room, and the communication opening defines the inner space of the inner tube portion and the muffling room. Communicating. Therefore, as in the case of the intake silencer of the first invention, only by connecting the intake duct and the intake system components,
A coaxial type resonator is formed, and intake pulsation noise can be suppressed. Moreover, when manufacturing this air intake silencer, it is possible to omit troublesome work steps such as a welding step and an insert molding step.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of an intake silencer according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of an intake duct and an air cleaner.

FIG. 3 is a perspective view of the air cleaner with an intake duct removed.

FIG. 4 is a sectional view of a second embodiment.

FIG. 5 is a sectional view of a third embodiment.

FIG. 6 is a sectional view of a fourth embodiment.

FIG. 7 is a sectional view of a conventional intake silencer;
7A is an explanatory diagram of a first conventional example, and FIG. 7B is an explanatory diagram of a second conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Air cleaner (intake system parts), 37 ... Intake duct connection opening, 38 ... Inner pipe, 38a ... Notch (communication opening), 39 ... Outer pipe, 41 ... Intake duct, 41a ... Intake duct main body, 43 ... Flange, 44: outer cylinder, 53: muffler chamber, 61: inner cylinder, 61a: notch (communication opening)

Claims (4)

[Claims] 1. An air intake duct having a single pipe duct main body, a ring-shaped flange provided at an end of the single pipe duct main body, and an outer cylinder protruding from an outer peripheral portion of the flange, and an air intake duct connection. And an intake pipe part comprising: an inner pipe projecting outward from an edge of the intake duct connection opening; and an outer pipe having a diameter larger than the diameter of the intake duct connection opening; When the intake duct and the intake system component are connected, an outer cylindrical portion of the intake duct and an outer pipe of the intake system component are fitted to each other, A double pipe structure is formed at the connection between the duct and the intake system component, and the outer cylinder part of the double pipe structure and the space between the outer pipe and the inner pipe serve as a sound deadening chamber, and the communication opening is formed inside. Between the internal space of the pipe and the silencer An intake silencer characterized by being in communication. 2. A fitting portion for fitting to an inner peripheral surface or an outer peripheral surface of a tip portion of the inner pipe is provided on the flange portion, and the communication opening is formed by a cutout portion formed at the tip of the inner pipe. The intake muffler according to claim 1, wherein 3. A duct body of a single pipe, a ring-shaped flange provided at an end of the duct body of the single pipe, an outer cylinder projecting from an outer periphery of the flange, and an inner periphery of the flange. An intake duct having an inner cylinder portion protruding; an intake duct connection opening; and an intake system component including an outer pipe having a diameter larger than the diameter of the intake duct connection opening; When the intake duct and the intake system component are connected, an outer cylindrical portion of the intake duct and an outer pipe of the intake system component are fitted, and the intake duct and the intake A double pipe structure is formed at the connection part with the system parts, and the space between the outer pipe part and the outer pipe and the inner pipe part of this double pipe structure becomes a sound deadening chamber,
The intake opening silencer, wherein the communication opening communicates the internal space of the inner cylinder with the silencing chamber. 4. An outer peripheral portion of the intake duct connection opening is provided with a fitting portion which is fitted to an inner peripheral surface or an outer peripheral surface of a distal end portion of the inner cylindrical portion, and the communication opening is provided at the distal end of the inner cylindrical portion. 4. The intake air silencer according to claim 3, wherein the air intake silencer is formed by a notch formed in the groove.